Conventional devices of this character comprise an endless band, perforated or not, on which the pieces of dough to be treated are deposited--usually in longitudinal rows--at an inlet end and from which they are removed at an outlet end. To hold these pieces in position between the two ends, at which the band is led around respective rollers, the band may be successively fitted at the inlet with lateral stops of limited length that are coupled together to form two parallel barriers between which the dough is confined. On arriving at the outlet, each strip is detached from the band and returned to the inlet end for reassembly. In order to entrain the pieces, the band is further equipped at its outer surface with longitudinally separated transverse flights which may also be temporarily coupled with the barrier-forming strips. Both the strips and the flights are usually made of steel-wire-reinforced wood which is known to avoid the risk of scorching of adjoining dough pieces upon passage through a high-temperature zone.
This type of arrangement, with its discontinuous mode of operation, is cumbersone and prevents an automated handling of the goods to be conveyed.
Test made with strips of polytetrafluoroethylene, mounted on hollow steel profiles for the circulation of cooling water, have shown this material to be less satisfactory than wood as far as the prevention of scorching is concerned.